diff --git a/.gitignore b/.gitignore index 0f86c21..ff8c99d 100644 --- a/.gitignore +++ b/.gitignore @@ -1,11 +1,6 @@ -# Do not know how to use -archive/ -Dockerfile - /models app.log *.pt -.venv/ # All pycache directories __pycache__/ diff --git a/CLAUDE.md b/CLAUDE.md new file mode 100644 index 0000000..3177259 --- /dev/null +++ b/CLAUDE.md @@ -0,0 +1,188 @@ +# Python Detector Worker - CLAUDE.md + +## Project Overview +This is a FastAPI-based computer vision detection worker that processes video streams from RTSP/HTTP sources and runs YOLO-based machine learning pipelines for object detection and classification. The system is designed to work within a larger CMS (Content Management System) architecture. + +## Architecture & Technology Stack +- **Framework**: FastAPI with WebSocket support +- **ML/CV**: PyTorch, Ultralytics YOLO, OpenCV +- **Containerization**: Docker (Python 3.13-bookworm base) +- **Data Storage**: Redis integration for action handling +- **Communication**: WebSocket-based real-time protocol + +## Core Components + +### Main Application (`app.py`) +- **FastAPI WebSocket server** for real-time communication +- **Multi-camera stream management** with shared stream optimization +- **HTTP REST endpoint** for image retrieval (`/camera/{camera_id}/image`) +- **Threading-based frame readers** for RTSP streams and HTTP snapshots +- **Model loading and inference** using MPTA (Machine Learning Pipeline Archive) format +- **Session management** with display identifier mapping +- **Resource monitoring** (CPU, memory, GPU usage via psutil) + +### Pipeline System (`siwatsystem/pympta.py`) +- **MPTA file handling** - ZIP archives containing model configurations +- **Hierarchical pipeline execution** with detection → classification branching +- **Redis action system** for image saving and message publishing +- **Dynamic model loading** with GPU optimization +- **Configurable trigger classes and confidence thresholds** + +### Testing & Debugging +- **Protocol test script** (`test_protocol.py`) for WebSocket communication validation +- **Pipeline webcam utility** (`pipeline_webcam.py`) for local testing with visual output +- **RTSP streaming debug tool** (`debug/rtsp_webcam.py`) using GStreamer + +## Code Conventions & Patterns + +### Logging +- **Structured logging** using Python's logging module +- **File + console output** to `detector_worker.log` +- **Debug level separation** for detailed troubleshooting +- **Context-aware messages** with camera IDs and model information + +### Error Handling +- **Graceful failure handling** with retry mechanisms (configurable max_retries) +- **Thread-safe operations** using locks for streams and models +- **WebSocket disconnect handling** with proper cleanup +- **Model loading validation** with detailed error reporting + +### Configuration +- **JSON configuration** (`config.json`) for runtime parameters: + - `poll_interval_ms`: Frame processing interval + - `max_streams`: Concurrent stream limit + - `target_fps`: Target frame rate + - `reconnect_interval_sec`: Stream reconnection delay + - `max_retries`: Maximum retry attempts (-1 for unlimited) + +### Threading Model +- **Frame reader threads** for each camera stream (RTSP/HTTP) +- **Shared stream optimization** - multiple subscriptions can reuse the same camera stream +- **Async WebSocket handling** with concurrent task management +- **Thread-safe data structures** with proper locking mechanisms + +## WebSocket Protocol + +### Message Types +- **subscribe**: Start camera stream with model pipeline +- **unsubscribe**: Stop camera stream processing +- **requestState**: Request current worker status +- **setSessionId**: Associate display with session identifier +- **patchSession**: Update session data +- **stateReport**: Periodic heartbeat with system metrics +- **imageDetection**: Detection results with timestamp and model info + +### Subscription Format +```json +{ + "type": "subscribe", + "payload": { + "subscriptionIdentifier": "display-001;cam-001", + "rtspUrl": "rtsp://...", // OR snapshotUrl + "snapshotUrl": "http://...", + "snapshotInterval": 5000, + "modelUrl": "http://...model.mpta", + "modelId": 101, + "modelName": "Vehicle Detection", + "cropX1": 100, "cropY1": 200, + "cropX2": 300, "cropY2": 400 + } +} +``` + +## Model Pipeline (MPTA) Format + +### Structure +- **ZIP archive** containing models and configuration +- **pipeline.json** - Main configuration file +- **Model files** - YOLO .pt files for detection/classification +- **Redis configuration** - Optional for action execution + +### Pipeline Flow +1. **Detection stage** - YOLO object detection with bounding boxes +2. **Trigger evaluation** - Check if detected class matches trigger conditions +3. **Classification stage** - Crop detected region and run classification model +4. **Action execution** - Redis operations (image saving, message publishing) + +### Branch Configuration +```json +{ + "modelId": "detector-v1", + "modelFile": "detector.pt", + "triggerClasses": ["car", "truck"], + "minConfidence": 0.5, + "branches": [{ + "modelId": "classifier-v1", + "modelFile": "classifier.pt", + "crop": true, + "triggerClasses": ["car"], + "minConfidence": 0.3, + "actions": [...] + }] +} +``` + +## Stream Management + +### Shared Streams +- Multiple subscriptions can share the same camera URL +- Reference counting prevents premature stream termination +- Automatic cleanup when last subscription ends + +### Frame Processing +- **Queue-based buffering** with single frame capacity (latest frame only) +- **Configurable polling interval** based on target FPS +- **Automatic reconnection** with exponential backoff + +## Development & Testing + +### Local Development +```bash +# Install dependencies +pip install -r requirements.txt + +# Run the worker +python app.py + +# Test protocol compliance +python test_protocol.py + +# Test pipeline with webcam +python pipeline_webcam.py --mpta-file path/to/model.mpta --video 0 +``` + +### Docker Deployment +```bash +# Build container +docker build -t detector-worker . + +# Run with volume mounts for models +docker run -p 8000:8000 -v ./models:/app/models detector-worker +``` + +### Testing Commands +- **Protocol testing**: `python test_protocol.py` +- **Pipeline validation**: `python pipeline_webcam.py --mpta-file --video 0` +- **RTSP debugging**: `python debug/rtsp_webcam.py` + +## Dependencies +- **fastapi[standard]**: Web framework with WebSocket support +- **uvicorn**: ASGI server +- **torch, torchvision**: PyTorch for ML inference +- **ultralytics**: YOLO implementation +- **opencv-python**: Computer vision operations +- **websockets**: WebSocket client/server +- **redis**: Redis client for action execution + +## Security Considerations +- Model files are loaded from trusted sources only +- Redis connections use authentication when configured +- WebSocket connections handle disconnects gracefully +- Resource usage is monitored to prevent DoS + +## Performance Optimizations +- GPU acceleration when CUDA is available +- Shared camera streams reduce resource usage +- Frame queue optimization (single latest frame) +- Model caching across subscriptions +- Trigger class filtering for faster inference \ No newline at end of file diff --git a/Dockerfile b/Dockerfile index f7c3612..fd55f68 100644 --- a/Dockerfile +++ b/Dockerfile @@ -1,20 +1,20 @@ -# Use newer, more secure base image -FROM python:3.13-alpine +# Use the official Python image from the Docker Hub +FROM python:3.13-bookworm -# Update system packages first -RUN apk update && apk upgrade +# Set the working directory in the container +WORKDIR /app -# Install minimal dependencies -RUN apk add --no-cache mesa-gl - -# Use specific package versions +# Copy the requirements file into the container at /app COPY requirements.txt . -RUN pip install --no-cache-dir --upgrade pip && \ - pip install --no-cache-dir -r requirements.txt -# Run as non-root user -RUN adduser -D -s /bin/sh appuser -USER appuser +# Update apt, install libgl1, and clear apt cache +RUN apt update && apt install -y libgl1 && rm -rf /var/lib/apt/lists/* +# Install any dependencies specified in requirements.txt +RUN pip install --no-cache-dir -r requirements.txt + +# Copy the rest of the application code into the container at /app COPY . . + +# Run the application CMD ["python3", "-m", "fastapi", "run", "--host", "0.0.0.0", "--port", "8000"] \ No newline at end of file diff --git a/app.py b/app.py index 5386496..60beb27 100644 --- a/app.py +++ b/app.py @@ -29,6 +29,12 @@ app = FastAPI() # "models" now holds a nested dict: { camera_id: { modelId: model_tree } } models: Dict[str, Dict[str, Any]] = {} streams: Dict[str, Dict[str, Any]] = {} +# Store session IDs per display +session_ids: Dict[str, int] = {} +# Track shared camera streams by camera URL +camera_streams: Dict[str, Dict[str, Any]] = {} +# Map subscriptions to their camera URL +subscription_to_camera: Dict[str, str] = {} with open("config.json", "r") as f: config = json.load(f) @@ -122,6 +128,15 @@ def fetch_snapshot(url: str): logger.error(f"Exception fetching snapshot from {url}: {str(e)}") return None +# Helper to get crop coordinates from stream +def get_crop_coords(stream): + return { + "cropX1": stream.get("cropX1"), + "cropY1": stream.get("cropY1"), + "cropX2": stream.get("cropX2"), + "cropY2": stream.get("cropY2") + } + #################################################### # REST API endpoint for image retrieval #################################################### @@ -133,20 +148,24 @@ async def get_camera_image(camera_id: str): try: with streams_lock: if camera_id not in streams: + logger.warning(f"Camera ID '{camera_id}' not found in streams. Current streams: {list(streams.keys())}") raise HTTPException(status_code=404, detail=f"Camera {camera_id} not found or not active") stream = streams[camera_id] buffer = stream["buffer"] + logger.debug(f"Camera '{camera_id}' buffer size: {buffer.qsize()}, buffer empty: {buffer.empty()}") + logger.debug(f"Buffer queue contents: {getattr(buffer, 'queue', None)}") if buffer.empty(): + logger.warning(f"No frame available for camera '{camera_id}'. Buffer is empty.") raise HTTPException(status_code=404, detail=f"No frame available for camera {camera_id}") # Get the latest frame (non-blocking) try: frame = buffer.queue[-1] # Get the most recent frame without removing it except IndexError: + logger.warning(f"Buffer queue is empty for camera '{camera_id}' when trying to access last frame.") raise HTTPException(status_code=404, detail=f"No frame available for camera {camera_id}") - # Encode frame as JPEG success, buffer_img = cv2.imencode('.jpg', frame, [cv2.IMWRITE_JPEG_QUALITY, 85]) if not success: @@ -171,9 +190,16 @@ async def detect(websocket: WebSocket): async def handle_detection(camera_id, stream, frame, websocket, model_tree, persistent_data): try: + # Apply crop if specified + cropped_frame = frame + if all(coord is not None for coord in [stream.get("cropX1"), stream.get("cropY1"), stream.get("cropX2"), stream.get("cropY2")]): + cropX1, cropY1, cropX2, cropY2 = stream["cropX1"], stream["cropY1"], stream["cropX2"], stream["cropY2"] + cropped_frame = frame[cropY1:cropY2, cropX1:cropX2] + logger.debug(f"Applied crop coordinates ({cropX1}, {cropY1}, {cropX2}, {cropY2}) to frame for camera {camera_id}") + logger.debug(f"Processing frame for camera {camera_id} with model {stream['modelId']}") start_time = time.time() - detection_result = run_pipeline(frame, model_tree) + detection_result = run_pipeline(cropped_frame, model_tree) process_time = (time.time() - start_time) * 1000 logger.debug(f"Detection for camera {camera_id} completed in {process_time:.2f}ms") @@ -222,22 +248,48 @@ async def detect(websocket: WebSocket): "box": [0, 0, 0, 0] } + # Convert detection format to match protocol - flatten detection attributes + detection_dict = {} + + # Handle different detection result formats + if isinstance(highest_confidence_detection, dict): + # Copy all fields from the detection result + for key, value in highest_confidence_detection.items(): + if key not in ["box", "id"]: # Skip internal fields + detection_dict[key] = value + + # Extract display identifier for session ID lookup + subscription_parts = stream["subscriptionIdentifier"].split(';') + display_identifier = subscription_parts[0] if subscription_parts else None + session_id = session_ids.get(display_identifier) if display_identifier else None + detection_data = { "type": "imageDetection", - "cameraIdentifier": camera_id, - "timestamp": time.time(), + "subscriptionIdentifier": stream["subscriptionIdentifier"], + "timestamp": time.strftime("%Y-%m-%dT%H:%M:%S.%fZ", time.gmtime()), "data": { - "detection": highest_confidence_detection, # Send only the highest confidence detection + "detection": detection_dict, "modelId": stream["modelId"], "modelName": stream["modelName"] } } + # Add session ID if available + if session_id is not None: + detection_data["sessionId"] = session_id + if highest_confidence_detection["class"] != "none": logger.info(f"Camera {camera_id}: Detected {highest_confidence_detection['class']} with confidence {highest_confidence_detection['confidence']:.2f} using model {stream['modelName']}") + + # Log session ID if available + subscription_parts = stream["subscriptionIdentifier"].split(';') + display_identifier = subscription_parts[0] if subscription_parts else None + session_id = session_ids.get(display_identifier) if display_identifier else None + if session_id: + logger.debug(f"Detection associated with session ID: {session_id}") await websocket.send_json(detection_data) - logger.debug(f"Sent detection data to client for camera {camera_id}:\n{json.dumps(detection_data, indent=2)}") + logger.debug(f"Sent detection data to client for camera {camera_id}") return persistent_data except Exception as e: logger.error(f"Error in handle_detection for camera {camera_id}: {str(e)}", exc_info=True) @@ -304,12 +356,11 @@ async def detect(websocket: WebSocket): if not buffer.empty(): try: buffer.get_nowait() - logger.debug(f"Removed old frame from buffer for camera {camera_id}") + logger.debug(f"[frame_reader] Removed old frame from buffer for camera {camera_id}") except queue.Empty: pass - buffer.put(frame) - logger.debug(f"Added new frame to buffer for camera {camera_id}") + logger.debug(f"[frame_reader] Added new frame to buffer for camera {camera_id}. Buffer size: {buffer.qsize()}") # Short sleep to avoid CPU overuse time.sleep(0.01) @@ -380,12 +431,11 @@ async def detect(websocket: WebSocket): if not buffer.empty(): try: buffer.get_nowait() - logger.debug(f"Removed old snapshot from buffer for camera {camera_id}") + logger.debug(f"[snapshot_reader] Removed old snapshot from buffer for camera {camera_id}") except queue.Empty: pass - buffer.put(frame) - logger.debug(f"Added new snapshot to buffer for camera {camera_id}") + logger.debug(f"[snapshot_reader] Added new snapshot to buffer for camera {camera_id}. Buffer size: {buffer.qsize()}") # Wait for the specified interval elapsed = time.time() - start_time @@ -456,18 +506,19 @@ async def detect(websocket: WebSocket): cpu_usage = psutil.cpu_percent() memory_usage = psutil.virtual_memory().percent if torch.cuda.is_available(): - gpu_usage = torch.cuda.memory_allocated() / (1024 ** 2) # MB - gpu_memory_usage = torch.cuda.memory_reserved() / (1024 ** 2) # MB + gpu_usage = torch.cuda.utilization() if hasattr(torch.cuda, 'utilization') else None + gpu_memory_usage = torch.cuda.memory_reserved() / (1024 ** 2) else: gpu_usage = None gpu_memory_usage = None camera_connections = [ { - "cameraIdentifier": camera_id, + "subscriptionIdentifier": stream["subscriptionIdentifier"], "modelId": stream["modelId"], "modelName": stream["modelName"], - "online": True + "online": True, + **{k: v for k, v in get_crop_coords(stream).items() if v is not None} } for camera_id, stream in streams.items() ] @@ -497,56 +548,70 @@ async def detect(websocket: WebSocket): if msg_type == "subscribe": payload = data.get("payload", {}) - camera_id = payload.get("cameraIdentifier") + subscriptionIdentifier = payload.get("subscriptionIdentifier") rtsp_url = payload.get("rtspUrl") snapshot_url = payload.get("snapshotUrl") - snapshot_interval = payload.get("snapshotInterval") # in milliseconds - model_url = payload.get("modelUrl") # may be remote or local + snapshot_interval = payload.get("snapshotInterval") + model_url = payload.get("modelUrl") modelId = payload.get("modelId") modelName = payload.get("modelName") + cropX1 = payload.get("cropX1") + cropY1 = payload.get("cropY1") + cropX2 = payload.get("cropX2") + cropY2 = payload.get("cropY2") + + # Extract camera_id from subscriptionIdentifier (format: displayIdentifier;cameraIdentifier) + parts = subscriptionIdentifier.split(';') + if len(parts) != 2: + logger.error(f"Invalid subscriptionIdentifier format: {subscriptionIdentifier}") + continue + + display_identifier, camera_identifier = parts + camera_id = subscriptionIdentifier # Use full subscriptionIdentifier as camera_id for mapping if model_url: with models_lock: if (camera_id not in models) or (modelId not in models[camera_id]): logger.info(f"Loading model from {model_url} for camera {camera_id}, modelId {modelId}") - extraction_dir = os.path.join("models", camera_id, str(modelId)) + extraction_dir = os.path.join("models", camera_identifier, str(modelId)) os.makedirs(extraction_dir, exist_ok=True) # If model_url is remote, download it first. parsed = urlparse(model_url) if parsed.scheme in ("http", "https"): - logger.info(f"Downloading remote model from {model_url}") - local_mpta = os.path.join(extraction_dir, os.path.basename(parsed.path)) + logger.info(f"Downloading remote .mpta file from {model_url}") + filename = os.path.basename(parsed.path) or f"model_{modelId}.mpta" + local_mpta = os.path.join(extraction_dir, filename) logger.debug(f"Download destination: {local_mpta}") local_path = download_mpta(model_url, local_mpta) if not local_path: - logger.error(f"Failed to download the remote mpta file from {model_url}") + logger.error(f"Failed to download the remote .mpta file from {model_url}") error_response = { "type": "error", - "cameraIdentifier": camera_id, + "subscriptionIdentifier": subscriptionIdentifier, "error": f"Failed to download model from {model_url}" } await websocket.send_json(error_response) continue model_tree = load_pipeline_from_zip(local_path, extraction_dir) else: - logger.info(f"Loading local model from {model_url}") + logger.info(f"Loading local .mpta file from {model_url}") # Check if file exists before attempting to load if not os.path.exists(model_url): - logger.error(f"Local model file not found: {model_url}") + logger.error(f"Local .mpta file not found: {model_url}") logger.debug(f"Current working directory: {os.getcwd()}") error_response = { "type": "error", - "cameraIdentifier": camera_id, + "subscriptionIdentifier": subscriptionIdentifier, "error": f"Model file not found: {model_url}" } await websocket.send_json(error_response) continue model_tree = load_pipeline_from_zip(model_url, extraction_dir) if model_tree is None: - logger.error(f"Failed to load model {modelId} from mpta file for camera {camera_id}") + logger.error(f"Failed to load model {modelId} from .mpta file for camera {camera_id}") error_response = { "type": "error", - "cameraIdentifier": camera_id, + "subscriptionIdentifier": subscriptionIdentifier, "error": f"Failed to load model {modelId}" } await websocket.send_json(error_response) @@ -555,95 +620,137 @@ async def detect(websocket: WebSocket): models[camera_id] = {} models[camera_id][modelId] = model_tree logger.info(f"Successfully loaded model {modelId} for camera {camera_id}") - success_response = { - "type": "modelLoaded", - "cameraIdentifier": camera_id, - "modelId": modelId - } - await websocket.send_json(success_response) + logger.debug(f"Model extraction directory: {extraction_dir}") if camera_id and (rtsp_url or snapshot_url): with streams_lock: + # Determine camera URL for shared stream management + camera_url = snapshot_url if snapshot_url else rtsp_url + if camera_id not in streams and len(streams) < max_streams: - buffer = queue.Queue(maxsize=1) - stop_event = threading.Event() + # Check if we already have a stream for this camera URL + shared_stream = camera_streams.get(camera_url) - # Choose between snapshot and RTSP based on availability - if snapshot_url and snapshot_interval: - logger.info(f"Using snapshot mode for camera {camera_id}: {snapshot_url}") - thread = threading.Thread(target=snapshot_reader, args=(camera_id, snapshot_url, snapshot_interval, buffer, stop_event)) - thread.daemon = True - thread.start() - streams[camera_id] = { - "buffer": buffer, - "thread": thread, - "snapshot_url": snapshot_url, - "snapshot_interval": snapshot_interval, - "stop_event": stop_event, - "modelId": modelId, - "modelName": modelName, - "mode": "snapshot" - } - logger.info(f"Subscribed to camera {camera_id} (snapshot mode) with modelId {modelId}, modelName {modelName}, URL {snapshot_url}, interval {snapshot_interval}ms") - elif rtsp_url: - logger.info(f"Using RTSP mode for camera {camera_id}: {rtsp_url}") - cap = cv2.VideoCapture(rtsp_url) - if not cap.isOpened(): - logger.error(f"Failed to open RTSP stream for camera {camera_id}") - continue - thread = threading.Thread(target=frame_reader, args=(camera_id, cap, buffer, stop_event)) - thread.daemon = True - thread.start() - streams[camera_id] = { - "cap": cap, - "buffer": buffer, - "thread": thread, - "rtsp_url": rtsp_url, - "stop_event": stop_event, - "modelId": modelId, - "modelName": modelName, - "mode": "rtsp" - } - logger.info(f"Subscribed to camera {camera_id} (RTSP mode) with modelId {modelId}, modelName {modelName}, URL {rtsp_url}") + if shared_stream: + # Reuse existing stream + logger.info(f"Reusing existing stream for camera URL: {camera_url}") + buffer = shared_stream["buffer"] + stop_event = shared_stream["stop_event"] + thread = shared_stream["thread"] + mode = shared_stream["mode"] + + # Increment reference count + shared_stream["ref_count"] = shared_stream.get("ref_count", 0) + 1 else: - logger.error(f"No valid URL provided for camera {camera_id}") - continue + # Create new stream + buffer = queue.Queue(maxsize=1) + stop_event = threading.Event() + + if snapshot_url and snapshot_interval: + logger.info(f"Creating new snapshot stream for camera {camera_id}: {snapshot_url}") + thread = threading.Thread(target=snapshot_reader, args=(camera_identifier, snapshot_url, snapshot_interval, buffer, stop_event)) + thread.daemon = True + thread.start() + mode = "snapshot" + + # Store shared stream info + shared_stream = { + "buffer": buffer, + "thread": thread, + "stop_event": stop_event, + "mode": mode, + "url": snapshot_url, + "snapshot_interval": snapshot_interval, + "ref_count": 1 + } + camera_streams[camera_url] = shared_stream + + elif rtsp_url: + logger.info(f"Creating new RTSP stream for camera {camera_id}: {rtsp_url}") + cap = cv2.VideoCapture(rtsp_url) + if not cap.isOpened(): + logger.error(f"Failed to open RTSP stream for camera {camera_id}") + continue + thread = threading.Thread(target=frame_reader, args=(camera_identifier, cap, buffer, stop_event)) + thread.daemon = True + thread.start() + mode = "rtsp" + + # Store shared stream info + shared_stream = { + "buffer": buffer, + "thread": thread, + "stop_event": stop_event, + "mode": mode, + "url": rtsp_url, + "cap": cap, + "ref_count": 1 + } + camera_streams[camera_url] = shared_stream + else: + logger.error(f"No valid URL provided for camera {camera_id}") + continue + + # Create stream info for this subscription + stream_info = { + "buffer": buffer, + "thread": thread, + "stop_event": stop_event, + "modelId": modelId, + "modelName": modelName, + "subscriptionIdentifier": subscriptionIdentifier, + "cropX1": cropX1, + "cropY1": cropY1, + "cropX2": cropX2, + "cropY2": cropY2, + "mode": mode, + "camera_url": camera_url + } + + if mode == "snapshot": + stream_info["snapshot_url"] = snapshot_url + stream_info["snapshot_interval"] = snapshot_interval + elif mode == "rtsp": + stream_info["rtsp_url"] = rtsp_url + stream_info["cap"] = shared_stream["cap"] + + streams[camera_id] = stream_info + subscription_to_camera[camera_id] = camera_url + elif camera_id and camera_id in streams: # If already subscribed, unsubscribe first - stream = streams.pop(camera_id) - stream["stop_event"].set() - stream["thread"].join() - if "cap" in stream: - stream["cap"].release() - logger.info(f"Unsubscribed from camera {camera_id} for resubscription") - with models_lock: - if camera_id in models and modelId in models[camera_id]: - del models[camera_id][modelId] - if not models[camera_id]: - del models[camera_id] + logger.info(f"Resubscribing to camera {camera_id}") + # Note: Keep models in memory for reuse across subscriptions elif msg_type == "unsubscribe": payload = data.get("payload", {}) - camera_id = payload.get("cameraIdentifier") - logger.debug(f"Unsubscribing from camera {camera_id}") + subscriptionIdentifier = payload.get("subscriptionIdentifier") + camera_id = subscriptionIdentifier with streams_lock: if camera_id and camera_id in streams: stream = streams.pop(camera_id) - stream["stop_event"].set() - stream["thread"].join() - # Only release cap if it exists (RTSP mode) - if "cap" in stream: - stream["cap"].release() - logger.info(f"Released RTSP capture for camera {camera_id}") - else: - logger.info(f"Released snapshot reader for camera {camera_id}") + camera_url = subscription_to_camera.pop(camera_id, None) + + if camera_url and camera_url in camera_streams: + shared_stream = camera_streams[camera_url] + shared_stream["ref_count"] -= 1 + + # If no more references, stop the shared stream + if shared_stream["ref_count"] <= 0: + logger.info(f"Stopping shared stream for camera URL: {camera_url}") + shared_stream["stop_event"].set() + shared_stream["thread"].join() + if "cap" in shared_stream: + shared_stream["cap"].release() + del camera_streams[camera_url] + else: + logger.info(f"Shared stream for {camera_url} still has {shared_stream['ref_count']} references") + logger.info(f"Unsubscribed from camera {camera_id}") - with models_lock: - if camera_id in models: - del models[camera_id] + # Note: Keep models in memory for potential reuse elif msg_type == "requestState": cpu_usage = psutil.cpu_percent() memory_usage = psutil.virtual_memory().percent if torch.cuda.is_available(): - gpu_usage = torch.cuda.memory_allocated() / (1024 ** 2) + gpu_usage = torch.cuda.utilization() if hasattr(torch.cuda, 'utilization') else None gpu_memory_usage = torch.cuda.memory_reserved() / (1024 ** 2) else: gpu_usage = None @@ -651,10 +758,11 @@ async def detect(websocket: WebSocket): camera_connections = [ { - "cameraIdentifier": camera_id, + "subscriptionIdentifier": stream["subscriptionIdentifier"], "modelId": stream["modelId"], "modelName": stream["modelName"], - "online": True + "online": True, + **{k: v for k, v in get_crop_coords(stream).items() if v is not None} } for camera_id, stream in streams.items() ] @@ -668,6 +776,37 @@ async def detect(websocket: WebSocket): "cameraConnections": camera_connections } await websocket.send_text(json.dumps(state_report)) + + elif msg_type == "setSessionId": + payload = data.get("payload", {}) + display_identifier = payload.get("displayIdentifier") + session_id = payload.get("sessionId") + + if display_identifier: + # Store session ID for this display + if session_id is None: + session_ids.pop(display_identifier, None) + logger.info(f"Cleared session ID for display {display_identifier}") + else: + session_ids[display_identifier] = session_id + logger.info(f"Set session ID {session_id} for display {display_identifier}") + + elif msg_type == "patchSession": + session_id = data.get("sessionId") + patch_data = data.get("data", {}) + + # For now, just acknowledge the patch - actual implementation depends on backend requirements + response = { + "type": "patchSessionResult", + "payload": { + "sessionId": session_id, + "success": True, + "message": "Session patch acknowledged" + } + } + await websocket.send_json(response) + logger.info(f"Acknowledged patch for session {session_id}") + else: logger.error(f"Unknown message type: {msg_type}") except json.JSONDecodeError: @@ -678,7 +817,6 @@ async def detect(websocket: WebSocket): except Exception as e: logger.error(f"Error handling message: {e}") break - try: await websocket.accept() stream_task = asyncio.create_task(process_streams()) @@ -691,19 +829,23 @@ async def detect(websocket: WebSocket): stream_task.cancel() await stream_task with streams_lock: - for camera_id, stream in streams.items(): - stream["stop_event"].set() - stream["thread"].join() - # Only release cap if it exists (RTSP mode) - if "cap" in stream: - stream["cap"].release() - while not stream["buffer"].empty(): + # Clean up shared camera streams + for camera_url, shared_stream in camera_streams.items(): + shared_stream["stop_event"].set() + shared_stream["thread"].join() + if "cap" in shared_stream: + shared_stream["cap"].release() + while not shared_stream["buffer"].empty(): try: - stream["buffer"].get_nowait() + shared_stream["buffer"].get_nowait() except queue.Empty: pass - logger.info(f"Released camera {camera_id} and cleaned up resources") + logger.info(f"Released shared camera stream for {camera_url}") + streams.clear() + camera_streams.clear() + subscription_to_camera.clear() with models_lock: models.clear() + session_ids.clear() logger.info("WebSocket connection closed") diff --git a/pympta.md b/pympta.md new file mode 100644 index 0000000..ac61f4a --- /dev/null +++ b/pympta.md @@ -0,0 +1,204 @@ +# pympta: Modular Pipeline Task Executor + +`pympta` is a Python module designed to load and execute modular, multi-stage AI pipelines defined in a special package format (`.mpta`). It is primarily used within the detector worker to run complex computer vision tasks where the output of one model can trigger a subsequent model on a specific region of interest. + +## Core Concepts + +### 1. MPTA Package (`.mpta`) + +An `.mpta` file is a standard `.zip` archive with a different extension. It bundles all the necessary components for a pipeline to run. + +A typical `.mpta` file has the following structure: + +``` +my_pipeline.mpta/ +├── pipeline.json +├── model1.pt +├── model2.pt +└── ... +``` + +- **`pipeline.json`**: (Required) The manifest file that defines the structure of the pipeline, the models to use, and the logic connecting them. +- **Model Files (`.pt`, etc.)**: The actual pre-trained model files (e.g., PyTorch, ONNX). The pipeline currently uses `ultralytics.YOLO` models. + +### 2. Pipeline Structure + +A pipeline is a tree-like structure of "nodes," defined in `pipeline.json`. + +- **Root Node**: The entry point of the pipeline. It processes the initial, full-frame image. +- **Branch Nodes**: Child nodes that are triggered by specific detection results from their parent. For example, a root node might detect a "vehicle," which then triggers a branch node to detect a "license plate" within the vehicle's bounding box. + +This modular structure allows for creating complex and efficient inference logic, avoiding the need to run every model on every frame. + +## `pipeline.json` Specification + +This file defines the entire pipeline logic. The root object contains a `pipeline` key for the pipeline definition and an optional `redis` key for Redis configuration. + +### Top-Level Object Structure + +| Key | Type | Required | Description | +| ---------- | ------ | -------- | ------------------------------------------------------- | +| `pipeline` | Object | Yes | The root node object of the pipeline. | +| `redis` | Object | No | Configuration for connecting to a Redis server. | + +### Redis Configuration (`redis`) + +| Key | Type | Required | Description | +| ---------- | ------ | -------- | ------------------------------------------------------- | +| `host` | String | Yes | The hostname or IP address of the Redis server. | +| `port` | Number | Yes | The port number of the Redis server. | +| `password` | String | No | The password for Redis authentication. | +| `db` | Number | No | The Redis database number to use. Defaults to `0`. | + +### Node Object Structure + +| Key | Type | Required | Description | +| ------------------- | ------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------- | +| `modelId` | String | Yes | A unique identifier for this model node (e.g., "vehicle-detector"). | +| `modelFile` | String | Yes | The path to the model file within the `.mpta` archive (e.g., "yolov8n.pt"). | +| `minConfidence` | Float | Yes | The minimum confidence score (0.0 to 1.0) required for a detection to be considered valid and potentially trigger a branch. | +| `triggerClasses` | Array | Yes | A list of class names that, when detected by the parent, can trigger this node. For the root node, this lists all classes of interest. | +| `crop` | Boolean | No | If `true`, the image is cropped to the parent's detection bounding box before being passed to this node's model. Defaults to `false`. | +| `branches` | Array | No | A list of child node objects that can be triggered by this node's detections. | +| `actions` | Array | No | A list of actions to execute upon a successful detection in this node. | + +### Action Object Structure + +Actions allow the pipeline to interact with Redis. They are executed sequentially for a given detection. + +#### Action Context & Dynamic Keys + +All actions have access to a dynamic context for formatting keys and messages. The context is created for each detection event and includes: + +- All key-value pairs from the detection result (e.g., `class`, `confidence`, `id`). +- `{timestamp_ms}`: The current Unix timestamp in milliseconds. +- `{uuid}`: A unique identifier (UUID4) for the detection event. +- `{image_key}`: If a `redis_save_image` action has already been executed for this event, this placeholder will be replaced with the key where the image was stored. + +#### `redis_save_image` + +Saves the current image frame (or cropped sub-image) to a Redis key. + +| Key | Type | Required | Description | +| ---------------- | ------ | -------- | ------------------------------------------------------------------------------------------------------- | +| `type` | String | Yes | Must be `"redis_save_image"`. | +| `key` | String | Yes | The Redis key to save the image to. Can contain any of the dynamic placeholders. | +| `expire_seconds` | Number | No | If provided, sets an expiration time (in seconds) for the Redis key. | + +#### `redis_publish` + +Publishes a message to a Redis channel. + +| Key | Type | Required | Description | +| --------- | ------ | -------- | ------------------------------------------------------------------------------------------------------- | +| `type` | String | Yes | Must be `"redis_publish"`. | +| `channel` | String | Yes | The Redis channel to publish the message to. | +| `message` | String | Yes | The message to publish. Can contain any of the dynamic placeholders, including `{image_key}`. | + +### Example `pipeline.json` with Redis + +This example demonstrates a pipeline that detects vehicles, saves a uniquely named image of each detection that expires in one hour, and then publishes a notification with the image key. + +```json +{ + "redis": { + "host": "redis.local", + "port": 6379, + "password": "your-super-secret-password" + }, + "pipeline": { + "modelId": "vehicle-detector", + "modelFile": "vehicle_model.pt", + "minConfidence": 0.6, + "triggerClasses": ["car", "truck"], + "actions": [ + { + "type": "redis_save_image", + "key": "detections:{class}:{timestamp_ms}:{uuid}", + "expire_seconds": 3600 + }, + { + "type": "redis_publish", + "channel": "vehicle_events", + "message": "{\"event\":\"new_detection\",\"class\":\"{class}\",\"confidence\":{confidence},\"image_key\":\"{image_key}\"}" + } + ], + "branches": [] + } +} +``` + +## API Reference + +The `pympta` module exposes two main functions. + +### `load_pipeline_from_zip(zip_source: str, target_dir: str) -> dict` + +Loads, extracts, and parses an `.mpta` file to build a pipeline tree in memory. It also establishes a Redis connection if configured in `pipeline.json`. + +- **Parameters:** + - `zip_source` (str): The file path to the local `.mpta` zip archive. + - `target_dir` (str): A directory path where the archive's contents will be extracted. +- **Returns:** + - A dictionary representing the root node of the pipeline, ready to be used with `run_pipeline`. Returns `None` if loading fails. + +### `run_pipeline(frame, node: dict, return_bbox: bool = False)` + +Executes the inference pipeline on a single image frame. + +- **Parameters:** + - `frame`: The input image frame (e.g., a NumPy array from OpenCV). + - `node` (dict): The pipeline node to execute (typically the root node returned by `load_pipeline_from_zip`). + - `return_bbox` (bool): If `True`, the function returns a tuple `(detection, bounding_box)`. Otherwise, it returns only the `detection`. +- **Returns:** + - The final detection result from the last executed node in the chain. A detection is a dictionary like `{'class': 'car', 'confidence': 0.95, 'id': 1}`. If no detection meets the criteria, it returns `None` (or `(None, None)` if `return_bbox` is `True`). + +## Usage Example + +This snippet, inspired by `pipeline_webcam.py`, shows how to use `pympta` to load a pipeline and process an image from a webcam. + +```python +import cv2 +from siwatsystem.pympta import load_pipeline_from_zip, run_pipeline + +# 1. Define paths +MPTA_FILE = "path/to/your/pipeline.mpta" +CACHE_DIR = ".mptacache" + +# 2. Load the pipeline from the .mpta file +# This reads pipeline.json and loads the YOLO models into memory. +model_tree = load_pipeline_from_zip(MPTA_FILE, CACHE_DIR) + +if not model_tree: + print("Failed to load pipeline.") + exit() + +# 3. Open a video source +cap = cv2.VideoCapture(0) + +while True: + ret, frame = cap.read() + if not ret: + break + + # 4. Run the pipeline on the current frame + # The function will handle the entire logic tree (e.g., find a car, then find its license plate). + detection_result, bounding_box = run_pipeline(frame, model_tree, return_bbox=True) + + # 5. Display the results + if detection_result: + print(f"Detected: {detection_result['class']} with confidence {detection_result['confidence']:.2f}") + if bounding_box: + x1, y1, x2, y2 = bounding_box + cv2.rectangle(frame, (x1, y1), (x2, y2), (0, 255, 0), 2) + cv2.putText(frame, detection_result['class'], (x1, y1 - 10), + cv2.FONT_HERSHEY_SIMPLEX, 0.9, (36, 255, 12), 2) + + cv2.imshow("Pipeline Output", frame) + + if cv2.waitKey(1) & 0xFF == ord('q'): + break + +cap.release() +cv2.destroyAllWindows() +``` \ No newline at end of file diff --git a/requirements.txt b/requirements.txt index 84f45cc..49ca601 100644 --- a/requirements.txt +++ b/requirements.txt @@ -5,4 +5,5 @@ torchvision ultralytics opencv-python websockets -fastapi[standard] \ No newline at end of file +fastapi[standard] +redis \ No newline at end of file diff --git a/siwatsystem/pympta.py b/siwatsystem/pympta.py index 5e32596..f151b55 100644 --- a/siwatsystem/pympta.py +++ b/siwatsystem/pympta.py @@ -7,13 +7,16 @@ import requests import zipfile import shutil import traceback +import redis +import time +import uuid from ultralytics import YOLO from urllib.parse import urlparse # Create a logger specifically for this module logger = logging.getLogger("detector_worker.pympta") -def load_pipeline_node(node_config: dict, mpta_dir: str) -> dict: +def load_pipeline_node(node_config: dict, mpta_dir: str, redis_client) -> dict: # Recursively load a model node from configuration. model_path = os.path.join(mpta_dir, node_config["modelFile"]) if not os.path.exists(model_path): @@ -44,13 +47,15 @@ def load_pipeline_node(node_config: dict, mpta_dir: str) -> dict: "triggerClassIndices": trigger_class_indices, "crop": node_config.get("crop", False), "minConfidence": node_config.get("minConfidence", None), + "actions": node_config.get("actions", []), "model": model, - "branches": [] + "branches": [], + "redis_client": redis_client } logger.debug(f"Configured node {node_config['modelId']} with trigger classes: {node['triggerClasses']}") for child in node_config.get("branches", []): logger.debug(f"Loading branch for parent node {node_config['modelId']}") - node["branches"].append(load_pipeline_node(child, mpta_dir)) + node["branches"].append(load_pipeline_node(child, mpta_dir, redis_client)) return node def load_pipeline_from_zip(zip_source: str, target_dir: str) -> dict: @@ -158,7 +163,26 @@ def load_pipeline_from_zip(zip_source: str, target_dir: str) -> dict: pipeline_config = json.load(f) logger.info(f"Successfully loaded pipeline configuration from {pipeline_json_path}") logger.debug(f"Pipeline config: {json.dumps(pipeline_config, indent=2)}") - return load_pipeline_node(pipeline_config["pipeline"], mpta_dir) + + # Establish Redis connection if configured + redis_client = None + if "redis" in pipeline_config: + redis_config = pipeline_config["redis"] + try: + redis_client = redis.Redis( + host=redis_config["host"], + port=redis_config["port"], + password=redis_config.get("password"), + db=redis_config.get("db", 0), + decode_responses=True + ) + redis_client.ping() + logger.info(f"Successfully connected to Redis at {redis_config['host']}:{redis_config['port']}") + except redis.exceptions.ConnectionError as e: + logger.error(f"Failed to connect to Redis: {e}") + redis_client = None + + return load_pipeline_node(pipeline_config["pipeline"], mpta_dir, redis_client) except json.JSONDecodeError as e: logger.error(f"Error parsing pipeline.json: {str(e)}", exc_info=True) return None @@ -169,6 +193,39 @@ def load_pipeline_from_zip(zip_source: str, target_dir: str) -> dict: logger.error(f"Error loading pipeline.json: {str(e)}", exc_info=True) return None +def execute_actions(node, frame, detection_result): + if not node["redis_client"] or not node["actions"]: + return + + # Create a dynamic context for this detection event + action_context = { + **detection_result, + "timestamp_ms": int(time.time() * 1000), + "uuid": str(uuid.uuid4()), + } + + for action in node["actions"]: + try: + if action["type"] == "redis_save_image": + key = action["key"].format(**action_context) + _, buffer = cv2.imencode('.jpg', frame) + expire_seconds = action.get("expire_seconds") + if expire_seconds: + node["redis_client"].setex(key, expire_seconds, buffer.tobytes()) + logger.info(f"Saved image to Redis with key: {key} (expires in {expire_seconds}s)") + else: + node["redis_client"].set(key, buffer.tobytes()) + logger.info(f"Saved image to Redis with key: {key}") + # Add the generated key to the context for subsequent actions + action_context["image_key"] = key + elif action["type"] == "redis_publish": + channel = action["channel"] + message = action["message"].format(**action_context) + node["redis_client"].publish(channel, message) + logger.info(f"Published message to Redis channel '{channel}': {message}") + except Exception as e: + logger.error(f"Error executing action {action['type']}: {e}") + def run_pipeline(frame, node: dict, return_bbox: bool=False): """ - For detection nodes (task != 'classify'): @@ -206,6 +263,7 @@ def run_pipeline(frame, node: dict, return_bbox: bool=False): "confidence": top1_conf, "id": None } + execute_actions(node, frame, det) return (det, None) if return_bbox else det @@ -254,9 +312,11 @@ def run_pipeline(frame, node: dict, return_bbox: bool=False): det2, _ = run_pipeline(sub, br, return_bbox=True) if det2: # return classification result + original bbox + execute_actions(br, sub, det2) return (det2, best_box) if return_bbox else det2 # ─── No branch matched → return this detection ───────────── + execute_actions(node, frame, best_det) return (best_det, best_box) if return_bbox else best_det except Exception as e: diff --git a/test_protocol.py b/test_protocol.py new file mode 100644 index 0000000..74af7d8 --- /dev/null +++ b/test_protocol.py @@ -0,0 +1,125 @@ +#!/usr/bin/env python3 +""" +Test script to verify the worker implementation follows the protocol +""" +import json +import asyncio +import websockets +import time + +async def test_protocol(): + """Test the worker protocol implementation""" + uri = "ws://localhost:8000" + + try: + async with websockets.connect(uri) as websocket: + print("✓ Connected to worker") + + # Test 1: Check if we receive heartbeat (stateReport) + print("\n1. Testing heartbeat...") + try: + message = await asyncio.wait_for(websocket.recv(), timeout=5) + data = json.loads(message) + if data.get("type") == "stateReport": + print("✓ Received stateReport heartbeat") + print(f" - CPU Usage: {data.get('cpuUsage', 'N/A')}%") + print(f" - Memory Usage: {data.get('memoryUsage', 'N/A')}%") + print(f" - Camera Connections: {len(data.get('cameraConnections', []))}") + else: + print(f"✗ Expected stateReport, got {data.get('type')}") + except asyncio.TimeoutError: + print("✗ No heartbeat received within 5 seconds") + + # Test 2: Request state + print("\n2. Testing requestState...") + await websocket.send(json.dumps({"type": "requestState"})) + try: + message = await asyncio.wait_for(websocket.recv(), timeout=5) + data = json.loads(message) + if data.get("type") == "stateReport": + print("✓ Received stateReport response") + else: + print(f"✗ Expected stateReport, got {data.get('type')}") + except asyncio.TimeoutError: + print("✗ No response to requestState within 5 seconds") + + # Test 3: Set session ID + print("\n3. Testing setSessionId...") + session_message = { + "type": "setSessionId", + "payload": { + "displayIdentifier": "display-001", + "sessionId": 12345 + } + } + await websocket.send(json.dumps(session_message)) + print("✓ Sent setSessionId message") + + # Test 4: Test patchSession + print("\n4. Testing patchSession...") + patch_message = { + "type": "patchSession", + "sessionId": 12345, + "data": { + "currentCar": { + "carModel": "Civic", + "carBrand": "Honda" + } + } + } + await websocket.send(json.dumps(patch_message)) + + # Wait for patchSessionResult + try: + message = await asyncio.wait_for(websocket.recv(), timeout=5) + data = json.loads(message) + if data.get("type") == "patchSessionResult": + print("✓ Received patchSessionResult") + print(f" - Success: {data.get('payload', {}).get('success')}") + print(f" - Message: {data.get('payload', {}).get('message')}") + else: + print(f"✗ Expected patchSessionResult, got {data.get('type')}") + except asyncio.TimeoutError: + print("✗ No patchSessionResult received within 5 seconds") + + # Test 5: Test subscribe message format (without actual camera) + print("\n5. Testing subscribe message format...") + subscribe_message = { + "type": "subscribe", + "payload": { + "subscriptionIdentifier": "display-001;cam-001", + "snapshotUrl": "http://example.com/snapshot.jpg", + "snapshotInterval": 5000, + "modelUrl": "http://example.com/model.mpta", + "modelName": "Test Model", + "modelId": 101, + "cropX1": 100, + "cropY1": 200, + "cropX2": 300, + "cropY2": 400 + } + } + await websocket.send(json.dumps(subscribe_message)) + print("✓ Sent subscribe message (will fail without actual camera/model)") + + # Listen for a few more messages to catch any errors + print("\n6. Listening for additional messages...") + for i in range(3): + try: + message = await asyncio.wait_for(websocket.recv(), timeout=2) + data = json.loads(message) + msg_type = data.get("type") + print(f" - Received {msg_type}") + if msg_type == "error": + print(f" Error: {data.get('error')}") + except asyncio.TimeoutError: + break + + print("\n✓ Protocol test completed successfully!") + + except Exception as e: + print(f"✗ Connection failed: {e}") + print("Make sure the worker is running on localhost:8000") + +if __name__ == "__main__": + asyncio.run(test_protocol()) \ No newline at end of file diff --git a/worker.md b/worker.md new file mode 100644 index 0000000..c50bae5 --- /dev/null +++ b/worker.md @@ -0,0 +1,483 @@ +# Worker Communication Protocol + +This document outlines the WebSocket-based communication protocol between the CMS backend and a detector worker. As a worker developer, your primary responsibility is to implement a WebSocket server that adheres to this protocol. + +## 1. Connection + +The worker must run a WebSocket server, preferably on port `8000`. The backend system, which is managed by a container orchestration service, will automatically discover and establish a WebSocket connection to your worker. + +Upon a successful connection from the backend, you should begin sending `stateReport` messages as heartbeats. + +## 2. Communication Overview + +Communication is bidirectional and asynchronous. All messages are JSON objects with a `type` field that indicates the message's purpose, and an optional `payload` field containing the data. + +- **Worker -> Backend:** You will send messages to the backend to report status, forward detection events, or request changes to session data. +- **Backend -> Worker:** The backend will send commands to you to manage camera subscriptions. + +## 3. Dynamic Configuration via MPTA File + +To enable modularity and dynamic configuration, the backend will send you a URL to a `.mpta` file when it issues a `subscribe` command. This file is a renamed `.zip` archive that contains everything your worker needs to perform its task. + +**Your worker is responsible for:** + +1. Fetching this file from the provided URL. +2. Extracting its contents. +3. Interpreting the contents to configure its internal pipeline. + +**The contents of the `.mpta` file are entirely up to the user who configures the model in the CMS.** This allows for maximum flexibility. For example, the archive could contain: + +- AI/ML Models: Pre-trained models for libraries like TensorFlow, PyTorch, or ONNX. +- Configuration Files: A `config.json` or `pipeline.yaml` that defines a sequence of operations, specifies model paths, or sets detection thresholds. +- Scripts: Custom Python scripts for pre-processing or post-processing. +- API Integration Details: A JSON file with endpoint information and credentials for interacting with third-party detection services. + +Essentially, the `.mpta` file is a self-contained package that tells your worker *how* to process the video stream for a given subscription. + +## 4. Messages from Worker to Backend + +These are the messages your worker is expected to send to the backend. + +### 4.1. State Report (Heartbeat) + +This message is crucial for the backend to monitor your worker's health and status, including GPU usage. + +- **Type:** `stateReport` +- **When to Send:** Periodically (e.g., every 2 seconds) after a connection is established. + +**Payload:** + +```json +{ + "type": "stateReport", + "cpuUsage": 75.5, + "memoryUsage": 40.2, + "gpuUsage": 60.0, + "gpuMemoryUsage": 25.1, + "cameraConnections": [ + { + "subscriptionIdentifier": "display-001;cam-001", + "modelId": 101, + "modelName": "General Object Detection", + "online": true, + "cropX1": 100, + "cropY1": 200, + "cropX2": 300, + "cropY2": 400 + } + ] +} +``` + +> **Note:** +> +> - `cropX1`, `cropY1`, `cropX2`, `cropY2` (optional, integer) should be included in each camera connection to indicate the crop coordinates for that subscription. + +### 4.2. Image Detection + +Sent when the worker detects a relevant object. The `detection` object should be flat and contain key-value pairs corresponding to the detected attributes. + +- **Type:** `imageDetection` + +**Payload Example:** + +```json +{ + "type": "imageDetection", + "subscriptionIdentifier": "display-001;cam-001", + "timestamp": "2025-07-14T12:34:56.789Z", + "data": { + "detection": { + "carModel": "Civic", + "carBrand": "Honda", + "carYear": 2023, + "bodyType": "Sedan", + "licensePlateText": "ABCD1234", + "licensePlateConfidence": 0.95 + }, + "modelId": 101, + "modelName": "US-LPR-and-Vehicle-ID" + } +} +``` + +### 4.3. Patch Session + +> **Note:** Patch messages are only used when the worker can't keep up and needs to retroactively send detections. Normally, detections should be sent in real-time using `imageDetection` messages. Use `patchSession` only to update session data after the fact. + +Allows the worker to request a modification to an active session's data. The `data` payload must be a partial object of the `DisplayPersistentData` structure. + +- **Type:** `patchSession` + +**Payload Example:** + +```json +{ + "type": "patchSession", + "sessionId": 12345, + "data": { + "currentCar": { + "carModel": "Civic", + "carBrand": "Honda", + "licensePlateText": "ABCD1234" + } + } +} +``` + +The backend will respond with a `patchSessionResult` command. + +#### `DisplayPersistentData` Structure + +The `data` object in the `patchSession` message is merged with the existing `DisplayPersistentData` on the backend. Here is its structure: + +```typescript +interface DisplayPersistentData { + progressionStage: "welcome" | "car_fueling" | "car_waitpayment" | "car_postpayment" | null; + qrCode: string | null; + adsPlayback: { + playlistSlotOrder: number; // The 'order' of the current slot + adsId: number | null; + adsUrl: string | null; + } | null; + currentCar: { + carModel?: string; + carBrand?: string; + carYear?: number; + bodyType?: string; + licensePlateText?: string; + licensePlateType?: string; + } | null; + fuelPump: { /* FuelPumpData structure */ } | null; + weatherData: { /* WeatherResponse structure */ } | null; + sessionId: number | null; +} +``` + +#### Patching Behavior + +- The patch is a **deep merge**. +- **`undefined`** values are ignored. +- **`null`** values will set the corresponding field to `null`. +- Nested objects are merged recursively. + +## 5. Commands from Backend to Worker + +These are the commands your worker will receive from the backend. + +### 5.1. Subscribe to Camera + +Instructs the worker to process a camera's RTSP stream using the configuration from the specified `.mpta` file. + +- **Type:** `subscribe` + +**Payload:** + +```json +{ + "type": "subscribe", + "payload": { + "subscriptionIdentifier": "display-001;cam-002", + "rtspUrl": "rtsp://user:pass@host:port/stream", + "snapshotUrl": "http://go2rtc/snapshot/1", + "snapshotInterval": 5000, + "modelUrl": "http://storage/models/us-lpr.mpta", + "modelName": "US-LPR-and-Vehicle-ID", + "modelId": 102, + "cropX1": 100, + "cropY1": 200, + "cropX2": 300, + "cropY2": 400 + } +} +``` + +> **Note:** +> +> - `cropX1`, `cropY1`, `cropX2`, `cropY2` (optional, integer) specify the crop coordinates for the camera stream. These values are configured per display and passed in the subscription payload. If not provided, the worker should process the full frame. +> +> **Important:** +> If multiple displays are bound to the same camera, your worker must ensure that only **one stream** is opened per camera. When you receive multiple subscriptions for the same camera (with different `subscriptionIdentifier` values), you should: +> +> - Open the RTSP stream **once** for that camera if using RTSP. +> - Capture each snapshot only once per cycle, and reuse it for all display subscriptions sharing that camera. +> - Capture each frame/image only once per cycle. +> - Reuse the same captured image and snapshot for all display subscriptions that share the camera, processing and routing detection results separately for each display as needed. +> This avoids unnecessary load and bandwidth usage, and ensures consistent detection results and snapshots across all displays sharing the same camera. + +### 5.2. Unsubscribe from Camera + +Instructs the worker to stop processing a camera's stream. + +- **Type:** `unsubscribe` + +**Payload:** + +```json +{ + "type": "unsubscribe", + "payload": { + "subscriptionIdentifier": "display-001;cam-002" + } +} +``` + +### 5.3. Request State + +Direct request for the worker's current state. Respond with a `stateReport` message. + +- **Type:** `requestState` + +**Payload:** + +```json +{ + "type": "requestState" +} +``` + +### 5.4. Patch Session Result + +Backend's response to a `patchSession` message. + +- **Type:** `patchSessionResult` + +**Payload:** + +```json +{ + "type": "patchSessionResult", + "payload": { + "sessionId": 12345, + "success": true, + "message": "Session updated successfully." + } +} +``` + +### 5.5. Set Session ID + +Allows the backend to instruct the worker to associate a session ID with a subscription. This is useful for linking detection events to a specific session. The session ID can be `null` to indicate no active session. + +- **Type:** `setSessionId` + +**Payload:** + +```json +{ + "type": "setSessionId", + "payload": { + "displayIdentifier": "display-001", + "sessionId": 12345 + } +} +``` + +Or to clear the session: + +```json +{ + "type": "setSessionId", + "payload": { + "displayIdentifier": "display-001", + "sessionId": null + } +} +``` + +> **Note:** +> +> - The worker should store the session ID for the given subscription and use it in subsequent detection or patch messages as appropriate. If `sessionId` is `null`, the worker should treat the subscription as having no active session. + +## Subscription Identifier Format + +The `subscriptionIdentifier` used in all messages is constructed as: + +``` +displayIdentifier;cameraIdentifier +``` + +This uniquely identifies a camera subscription for a specific display. + +### Session ID Association + +When the backend sends a `setSessionId` command, it will only provide the `displayIdentifier` (not the full `subscriptionIdentifier`). + +**Worker Responsibility:** + +- The worker must match the `displayIdentifier` to all active subscriptions for that display (i.e., all `subscriptionIdentifier` values that start with `displayIdentifier;`). +- The worker should set or clear the session ID for all matching subscriptions. + +## 6. Example Communication Log + +This section shows a typical sequence of messages between the backend and the worker. Patch messages are not included, as they are only used when the worker cannot keep up. + +> **Note:** Unsubscribe is triggered when a user removes a camera or when the node is too heavily loaded and needs rebalancing. + +1. **Connection Established** & **Heartbeat** + * **Worker -> Backend** + ```json + { + "type": "stateReport", + "cpuUsage": 70.2, + "memoryUsage": 38.1, + "gpuUsage": 55.0, + "gpuMemoryUsage": 20.0, + "cameraConnections": [] + } + ``` +2. **Backend Subscribes Camera** + * **Backend -> Worker** + ```json + { + "type": "subscribe", + "payload": { + "subscriptionIdentifier": "display-001;entry-cam-01", + "rtspUrl": "rtsp://192.168.1.100/stream1", + "modelUrl": "http://storage/models/vehicle-id.mpta", + "modelName": "Vehicle Identification", + "modelId": 201 + } + } + ``` +3. **Worker Acknowledges in Heartbeat** + * **Worker -> Backend** + ```json + { + "type": "stateReport", + "cpuUsage": 72.5, + "memoryUsage": 39.0, + "gpuUsage": 57.0, + "gpuMemoryUsage": 21.0, + "cameraConnections": [ + { + "subscriptionIdentifier": "display-001;entry-cam-01", + "modelId": 201, + "modelName": "Vehicle Identification", + "online": true + } + ] + } + ``` +4. **Worker Detects a Car** + * **Worker -> Backend** + ```json + { + "type": "imageDetection", + "subscriptionIdentifier": "display-001;entry-cam-01", + "timestamp": "2025-07-15T10:00:00.000Z", + "data": { + "detection": { + "carBrand": "Honda", + "carModel": "CR-V", + "bodyType": "SUV", + "licensePlateText": "GEMINI-AI", + "licensePlateConfidence": 0.98 + }, + "modelId": 201, + "modelName": "Vehicle Identification" + } + } + ``` + * **Worker -> Backend** + ```json + { + "type": "imageDetection", + "subscriptionIdentifier": "display-001;entry-cam-01", + "timestamp": "2025-07-15T10:00:01.000Z", + "data": { + "detection": { + "carBrand": "Toyota", + "carModel": "Corolla", + "bodyType": "Sedan", + "licensePlateText": "CMS-1234", + "licensePlateConfidence": 0.97 + }, + "modelId": 201, + "modelName": "Vehicle Identification" + } + } + ``` + * **Worker -> Backend** + ```json + { + "type": "imageDetection", + "subscriptionIdentifier": "display-001;entry-cam-01", + "timestamp": "2025-07-15T10:00:02.000Z", + "data": { + "detection": { + "carBrand": "Ford", + "carModel": "Focus", + "bodyType": "Hatchback", + "licensePlateText": "CMS-5678", + "licensePlateConfidence": 0.96 + }, + "modelId": 201, + "modelName": "Vehicle Identification" + } + } + ``` +5. **Backend Unsubscribes Camera** + * **Backend -> Worker** + ```json + { + "type": "unsubscribe", + "payload": { + "subscriptionIdentifier": "display-001;entry-cam-01" + } + } + ``` +6. **Worker Acknowledges Unsubscription** + * **Worker -> Backend** + ```json + { + "type": "stateReport", + "cpuUsage": 68.0, + "memoryUsage": 37.0, + "gpuUsage": 50.0, + "gpuMemoryUsage": 18.0, + "cameraConnections": [] + } + ``` +## 7. HTTP API: Image Retrieval + +In addition to the WebSocket protocol, the worker exposes an HTTP endpoint for retrieving the latest image frame from a camera. + +### Endpoint + +``` +GET /camera/{camera_id}/image +``` + +- **`camera_id`**: The full `subscriptionIdentifier` (e.g., `display-001;cam-001`). + +### Response + +- **Success (200):** Returns the latest JPEG image from the camera stream. + - `Content-Type: image/jpeg` + - Binary JPEG data. + +- **Error (404):** If the camera is not found or no frame is available. + - JSON error response. + +- **Error (500):** Internal server error. + +### Example Request + +``` +GET /camera/display-001;cam-001/image +``` + +### Example Response + +- **Headers:** + ``` + Content-Type: image/jpeg + ``` +- **Body:** Binary JPEG image. + +### Notes + +- The endpoint returns the most recent frame available for the specified camera subscription. +- If multiple displays share the same camera, each subscription has its own buffer; the endpoint uses the buffer for the given `camera_id`. +- This API is useful for debugging, monitoring, or integrating with external systems that require direct image access.